1/*
2 * This file is part of inet-yy strace test.
3 *
4 * Copyright (c) 2014-2016 Dmitry V. Levin <ldv@altlinux.org>
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 *    notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 *    notice, this list of conditions and the following disclaimer in the
14 *    documentation and/or other materials provided with the distribution.
15 * 3. The name of the author may not be used to endorse or promote products
16 *    derived from this software without specific prior written permission.
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
19 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
20 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
21 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
22 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
23 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
24 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
25 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
26 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
27 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
28 */
29
30#include "tests.h"
31#include <errno.h>
32#include <string.h>
33#include <unistd.h>
34#include <netinet/in.h>
35#include <linux/netlink.h>
36#include <linux/sock_diag.h>
37#include <linux/inet_diag.h>
38
39static void
40send_query(const int fd, const int family, const int proto)
41{
42	struct sockaddr_nl nladdr = {
43		.nl_family = AF_NETLINK
44	};
45	struct {
46		struct nlmsghdr nlh;
47		struct inet_diag_req_v2 idr;
48	} req = {
49		.nlh = {
50			.nlmsg_len = sizeof(req),
51			.nlmsg_type = SOCK_DIAG_BY_FAMILY,
52			.nlmsg_flags = NLM_F_DUMP | NLM_F_REQUEST
53		},
54		.idr = {
55			.sdiag_family = family,
56			.sdiag_protocol = proto,
57			.idiag_states = -1
58		}
59	};
60	struct iovec iov = {
61		.iov_base = &req,
62		.iov_len = sizeof(req)
63	};
64	struct msghdr msg = {
65		.msg_name = (void *) &nladdr,
66		.msg_namelen = sizeof(nladdr),
67		.msg_iov = &iov,
68		.msg_iovlen = 1
69	};
70
71	if (sendmsg(fd, &msg, 0) <= 0)
72		perror_msg_and_skip("sendmsg");
73}
74
75static void
76check_responses(const int fd)
77{
78	static union {
79		struct nlmsghdr hdr;
80		long buf[8192 / sizeof(long)];
81	} hdr_buf;
82
83	struct sockaddr_nl nladdr = {
84		.nl_family = AF_NETLINK
85	};
86	struct iovec iov = {
87		.iov_base = hdr_buf.buf,
88		.iov_len = sizeof(hdr_buf.buf)
89	};
90	struct msghdr msg = {
91		.msg_name = (void *) &nladdr,
92		.msg_namelen = sizeof(nladdr),
93		.msg_iov = &iov,
94		.msg_iovlen = 1
95	};
96
97	ssize_t ret = recvmsg(fd, &msg, 0);
98	if (ret <= 0)
99		perror_msg_and_skip("recvmsg");
100
101	struct nlmsghdr *h = &hdr_buf.hdr;
102	if (!NLMSG_OK(h, ret))
103		error_msg_and_skip("!NLMSG_OK");
104	if (h->nlmsg_type == NLMSG_ERROR) {
105		const struct nlmsgerr *err = NLMSG_DATA(h);
106		if (h->nlmsg_len < NLMSG_LENGTH(sizeof(*err)))
107			error_msg_and_skip("NLMSG_ERROR");
108		errno = -err->error;
109		perror_msg_and_skip("NLMSG_ERROR");
110	}
111	if (h->nlmsg_type != SOCK_DIAG_BY_FAMILY)
112		error_msg_and_skip("unexpected nlmsg_type %u",
113				   (unsigned) h->nlmsg_type);
114
115	const struct inet_diag_msg *diag = NLMSG_DATA(h);
116	if (h->nlmsg_len < NLMSG_LENGTH(sizeof(*diag)))
117		error_msg_and_skip("short response");
118}
119
120int main(void)
121{
122	struct sockaddr_in addr;
123	socklen_t len = sizeof(addr);
124
125	memset(&addr, 0, sizeof(addr));
126	addr.sin_family = AF_INET;
127	addr.sin_addr.s_addr = htonl(INADDR_LOOPBACK);
128
129	close(0);
130	close(1);
131
132	if (socket(AF_INET, SOCK_STREAM, 0))
133		perror_msg_and_skip("socket AF_INET");
134	if (bind(0, (struct sockaddr *) &addr, len))
135		perror_msg_and_skip("bind");
136	if (listen(0, 5))
137		perror_msg_and_skip("listen");
138	if (socket(AF_NETLINK, SOCK_RAW, NETLINK_INET_DIAG) != 1)
139		perror_msg_and_skip("socket AF_NETLINK");
140
141	send_query(1, AF_INET, IPPROTO_TCP);
142	check_responses(1);
143	return 0;
144}
145